6.5 X 55 swede, M-96 military mauser barrel cut to 21" coned, stock bedded, bolt turned down, timney target trigger installed, and a CHEAP scope. When I shot it a number of years ago the groups were literally the size of a dime at 100 yards. I couldn't believe my eyes on this one. Since then I've heard of others having the same results with this type of rifle.http://www.youtube.com/watch?v=MpjIK...eature=related

Savage 93R17--17HMR, another tack driver.

Honorable mention is the H&R ultra varmit bull barrel .223. I had to work my buns off on this one to get it to shoot right. (float fore arm, reduce trigger pull, fire lap the barrel)